Two-Dimensional Growth of CdSe Nanocrystals, from Nanoplatelets to Nanosheets

Abstract

We report the continuous lateral extension of cadmium selenide nanoplatelets into nanosheets using continuous injection of precursors at high temperature. We show that we can obtain CdSe nanosheets with lateral dimensions up to 700 nm and a well-defined thickness that can be tuned with atomic precision. When the nanosheets’ lateral size increases, they roll on themselves to form nanoscrolls that can unroll upon surface modification. The final geometry of the nanosheets can be tuned to different morphologies using precursors that favor the growth of specific crystal facets. We provide a detailed study of the CdSe nanosheets growth and its optimization for three different thicknesses.